Dampener for printing presses



Feb. 22, 1938. E. c. GREMBECKI DAMPENER FOR PRINTING PRESSES s sheets-sheet 2.

Filed Aug. 29, 1936 INVENTOR. Elmer C. Gremfiecfii H1 6' ATTORNEY.

Feb. 22, 1938. E. c. GREMBECKI 2,108,984

DAMPENER FOR PRINTING PRESSES Filed Aug. 29, 1936 s Sheets-Sheet s INVENTOR- E'lmer 6'. Grembecfii H16 ATTORNEY:

Patented Feb. 22, 1938 DAMPENEE FOR PRINTING PRESSES Eim'er C. Grembecki, Chicago, Ill.

Application August 29, 1936, Serial No. 98,451

Claims.

This invention concerns the artoi printing and particularly lithographic printing, and one of its important objects is the provision of a novel dampener for a lithographic offset press.

Generally stated, the invention provides a;

novel, compact, rugged and inexpensively manufactured dampening mechanism which includes a U-shaped blower tube for positioning relative to the plate cylinder of the press, means for establishing a water "spray in the lower part of the tube, power driven means for atomizing the spray water, a blower device for distributing the atom; ized water over the cylinder, and an automatic gate or shutter mechanism for controlling the distribution of the atomized water or dampening agent with relation to the plate cylinder, together with auxiliary control and operating means to be hereinafter particularly described and suchv other novel eiementsof structure and operating features as will appear in view of the annexed drawings in which:

Fig. l is a side elevation of a form of offset press utilizing the novel dampener means;

Fig. 2 is a top plan view along lines 2-2 of Fig. 1 and to larger scale;

Fig. 3 is a median vertical section along lines 3-3 of Fig. 2 and to larger scale;

Fig. 4 is an enlarged vertical fragment partly in section, looking toward lines 4-4 of Fig. 3;

Fig. 5 is an operating detail of the gage cam finger taken in the direction of lines 5-5 of Fig. 2;

Fig. 6 shows the gear scheme for driving the atomizer from the plate cylinder, and is takenalong lines 6-6 of Fig. 2;

Fig. 7 is a vertical section detail of the atomizer-shaft bearing structure;

Fig. 8 is an elevation detail of the blower line,

. taken along lines 8-8 of Fig. 3;

. secure opposite extremities of the plate over iongituclinally extensive edge portions 24 of an axially extended side opening'j 26 in the cylinder wall. Above the plate cylinder, and bearing against the plate 20, are a number of ink rollers 28 adapted to apply ink to the surface of the plate as it rotates against an impression roller 30 the rubberized surface of which retains the ink received from the etched plate in the particular printing 5 outline or configuration of the latter.

A paper feeding or skeleton roller 32 urges a continuous sheet of paper stock 34 against the ink-patterned surface .of the impression roller 30, and the printed" sheet 35 is threaded out of 1 the press over roller 36.

The "printing or lithograph plate 20 has its active surface etched in the outline of whatever characters or. delineations are to be printed, and in order to make the printing ink adhere to the 15 unetched surfaces and to prevent it from entering the etched or cut-away portions, water or other suitable liquid is applied to the plate as it rotates from printing to inking position so that the etched crevices retainthe water while the solid surfaces do not, and thus the ink (which desirablyis not water soluble) is prevented from en- 7 tering the etched parts of the plate, while the unetched surfaces to which the water does not cling are inked.

Heretofore, it has been the practive to apply the water by a sort of sponging process which involved the use of a-speci'al roller carrying a water retaining blanket of especially suitable fibrous material, the blanket being pressed against the 30 plate as it rolled from impression position toward the inking rollers.

This dampening expedient is subject to a num ber of serious objections, among others, the fact that the blankets retain ink from the plate and 35 rapidly decrease in dampening'efllciency; moreover, since the ink is variously distributed, the dampening efliciency of the blanket is not uniform throughout its length. Thus the blankets must frequently be changed and discarded, and 40 for this purpose the press must be stopped, so that, at its best, the blanket is not an ideal or reliable dampening means.

The present invention does away with the foregoing method and means by providing the dampener mechanism generally indicated at 40 (Fig. 1), which includes an elongated, U-shaped duct member or tube 42 having a constricted upper arm or branch 44 (Fig. 3) with a longitudie. nally extensive edgewise exhaust opening 46, hav- 5o ing its uppermost longitudinal edge curved to form a lip 48 which closely overlies the plate 20 on cylinder l8; and having its lower edge 49 also closely positioned with respect to the plate.

The lower branch 45 of the atomizer or damp- 2- enlng tube is enlarged or flared outwardly'below the bight I! oi the U-tube, and the lowermost wall portion thereof has a longitudinally extended trough l intowhich extends a curved trough 58 at its lower end. The entire U-tube struc ture is adapted to be securely mounted on the press frame by suitable brackets and cross bar structure (Fig. 3).

The longitudinal edge opening of the lower branch of the dampening or U-structure is closed by an apertured baffle plate 58 over which is secured an air duct 59 communicating at its lefthand extremity (Figs. 1 to 4, and 8) with a blowerline 82 which in turn is connected to a suitable power driven blower (Fig. 1). A gauge and relief cock unit BI is provided at the opposite (right-hand) end of the blower duct (Fig. 8) for supervision of the air pressure.

Extended across the upper surface of the lower arm of the atomizer tube is an elongated, open water feed trough 64 which may be seated on a pair of T-beams 86 riveted to upturned wall portions 62 of the tube wall. The bottom wall of this trough N is suitably apertured to provide a plurality of water sprays, indicated at I0, across the breadth'and length of the atomizer tube above trough 50.

Rotatable with a longitudinally extended shaft 'i2.secured to a hub structure II is an atomiz: ing or water chopping P ddle I6, which includes a plurality of apertured mesh or screen blades ll secured to the hub 14 and end plates I (Fig. 7). This atomizing paddle is interposed between the bottom wall of trough 84 andthe tube trough 52 so that its blades intercept the spray jets I0,

upon rotation of the shaft If! in hearing plates 80 which are secured with and closure plates 22 to the tube body.

Opening into the right-hand end of the feed through trough 84 (Fig. l.) is a water supply pipe 5 from a circulating pump 84, while an overflow pipe 88 extends from the opposite end wall thereof to a drain or reservoir, as desired.

It is desirable that the atomizing paddles be revolved at a relatively high speed. to eifect a iine-break-up of the water spray, and to this end i I have provided a mechanism for driving the atomizer from a master gear 88 on the plate cylinder I! through a gear train 90-92-84 suitably carried in shaft brackets 96' and 98 attached to frame member 4|. The speed of the plate cylinder mayconveniently be taken as 60 R. P. 11., and the gear train is adapted to drive the chopper shaft I2 at approximately 1500 R. P. M., at which speed the water is adequately broken up into a fine mist.

The upper branch 44 of the atomizer tube is provided adjacent its exhaust end 4! with a plu-' rality of adjustable baille plates Ill (Figs. 1, 4) extended transversely of theduct passages along the length of the tube. These ba'filepiates have handle extensions. I02 and are slidable vertically between upstanding confronting extensions I" from the top wall of upper tube l4; and in order to maintain a given plate in-a given vertical position, concavities III. are provided in vertical alignment for yieldable latching engagement by a spring urged presser bait-I".

the baille plate III. is 'a cylinder-shaped shutter gate III having a pair of opp site side wall openings H2 and rotatably supported by spindles Ill and Ill which extend from end plates II 8 in the cylinder through the end walls H6 and IIS' respectively of the upper branch of the atomizer tube (Fig. 2). The shaft IIl extends beyond end wall I I6 into a hanger bracket II8 on frame member 4i (bottom of Fig. 2).

It will be recalled that the-plate cylinder I8 has a relatively wide axially extensive opening 28 to facilitate mounting and clamping the impression plate, and in order to prevent water being driven into this opening, when it revolves into position before the exhaust end 56 of upper tube 42, a reciprocating drive connection is effected to a cam I20 (Figs. 1 and 5) on plate cylinder shaft II, by. means .of a presser rod I22 slidable in a bracket I26, which is part of the hanger bracket H8, and against the tension of a spring I24 attached to the bracket I28 and to the rod I22 on pin I28 and connecting pin I29, respectively.

One-extremity of the presser rod I22 is pivotally connected as at I39 to an eccentric coupling I32 on shaft ill, and has at its other extremity a roller I34 which bears against the face of the cam I so asto rock shutter III! through the shaft I from open to closed position at determined intervals.

The shutter member iIII extends beyond both the upper and lower wall portions of the upper branch of the atomizer tube as will appear from Fig. 3, and attached to the bottom wall underlying the bottom of the shutter cylinder is a downwardly inclined drip apron M0 which terminates over the trough 64 and serves to drain the condensation water from both the baffles IIII and shutter Ilil. A second and smaller drip. apron M2 extends oppositely to the firstapron from a depending plate ill on the tube body and has its drip edge overlying the edge of plate lei).

On the upper wall of the upper tube arm opposite to the drip aprons I48I42 is an exchopper may be keyed to a drive shaft I58 by a set screw I56, the drive shaft corresponding to shaft I2 of Fig. 3, for example.

Each of the discs in is provided with a plurality of ears or fins I which may be extruded from, or formed upon, the plane faces of the several plates in varying patterns, other than that shown in Fig. 10.

If desired, the rotary atomizing mechanism maybe omitted, as shown in the modification of Fig. 11, in which case the general tube structure will otherwise be the same, except that the air pressure in duct 60' will necessarily be ma-fl terlally increased and the apertures in baflleplate 58' will .be reduced in dimension in corre-- sponding ratio to provide a plurality of line can-- 'ergetic air jets to break up the water-sprays III from the overhead feed trough "in atomizer tube 42'. Another arrangement for the'atomizing mechanism and. one-which gives excellent results may belaeaslly achieved by closing off the drain it,

screwed in in place of the screw plug now shown (Fig. 4). Under these conditions, water-will remain in the trough 5D and it is desirable to When this arrangement is utilized, the best results are achieved by using the chopper of Fig. 10

in place of the device of Fig. 7.

Operation Referring particularly to Figs. 1 and 3, the plate cylinder I8 will be rotated by the usual power means. and the etched plate 20 carried therewith will move in an anti-clockwise direction toward the dampening mechanism til and be rotated past the horizontally extensive exhaust opening 46 of the upper branch M of the atomizing tube structure.

Meanwhile the atomizer blower mechanism 64 (Figs. 1 and 2) has been set in motion and an air pressure of approximately 4 pounds set up in the duct 60, forcing air through the apertured baffle plate I over and through the atomizing or chopping paddles 18.

The water pump 8 which may be provided with necessary automatic controls, will deliver water, which is preferably acidulated, through pipe 65 into the open trough 61 to maintain a suitable head therein in cooperation with the overflow line 86.

This water will descend through the apertured bottom of the trough in a plurality of sprays "l0 which will be rapidly intercepted or chopped by the rotating screen, or equivalent, paddles it carried about by the shaft 12 which is driven at relatively high speed by the gear train 88-436-42-96 powered through the rotating plate cylinder.

If the modified form of chopper discs of Figs. 9 and 10 are used, the laterally extending cars or fins lStl will heat into the watersprays and break up the water in similar manner.

Meanwhile a plurality of air jets or streams will be issuing from the apertures in baiiie plate and passing through the openings in the screening or mesh of the paddles it, thus further break- -ing up the water and driving the atomized particles around the bght 4'! of tube 42 into the upper arm at.

The operation of the modified structure of Fig. 11, which omits the mechanical chopper, relies upon the interacting air jets and water sprays to efiect an adequate break-up of the water, the air being supplied under higher pressure than otherwise necessary (e. g. 25 lbs.).

The water particles will be driven upwardly against the outer bight part 41 of the wall of the U-tube, and the heavier particles will tend to collect and drop back into the trough 50 through pan 5G to pass out through theinclined drain trough 5| and drain 5%. Such condensationof the finer mist which occurs will be disposed of similarly.'

Such of the finer water particles as enter the upper branch 44 of the tubewill pass through the aligned openings H2 in shutter H0 (still referring to Fig. 3) andimpinge against any portion of the adjustable bailie plates IBll which may have been positioned to lie 'in' thepath thereof. Particles deflected'by the baffle plates will pass downwardly over the apron hand into trough 84, while the unimpeded atomized particles will be carried and directed bythe outwardly moving air current against the rotating plate 20 on cylinder H3, in a uniform quantity highly suitable for moistening the etched plate in the manner and forv the purpose hereinbefore set forth.

When a plate 20 of reduced width is clamped on the cylinder la, the baflles iM may be lowered along a line parallel to the axis of the cylinder and thus limit the dampening field.

As the plate cylinder rotates through its'cycie the axial opening 26 therein will approach (counter-clockwise) the mouth or exhaust end to of the dampening tube, and at this juncture the cam E20 or cylinder shaft I! (Fig. 5) will approach the presser finger I22 and thereafter urge the latter outwardly against its spring 124 to rock the shaft ii through the eccentric coupling 832, whereupon the shutter ill! will be pivoted by shaft lit to close the upper delivery branch Q6 of the tube 42 so that none of the moisture will be driven into the cylinder opening. As the cylinder proceeds the shutter i it will again be opened by further movement of cam I20 against finger 522, in timed relation to the next positioning of the plate 20. In this manner the exhaust side of the atomizer is alternately opened and closed.

Where the mechanical chopping mechanism is omitted and the air pressure increased in accord- .30

ance with the showing of Fig. 11, the operation so far as it applies to the elements not omitted. is substantially the same.

In general it is observed that the combined 00-- operative effect of the air moving means with the spray and propelling or chopping devices, together with the particular form of the atomizer tube, are all important in providing suitably div'dcd water particles in adequate quantity and depositing the same uniformly and under control on the lithograph plate.

While I have described the means of my invention in detail, I do not intend to be confined to any particular recitations or limitations except as may be hereinafter provided in the annexed claims.

1. Dampening mechanism for printing presses and the like comprising a housing having an opening for*confrontation with a press plate cylinder, means providing a water spray in said housing, a power driven propeller supported within the housing and having a plurality of apertured arms rotatable to intercept said sprays and break up the water into fine particles, together with means for moving air past said propeller means in said housing to carry said particle's through said opening on to said cylinder.

2. A dampening mechanism in accordance with claim 1 and further characterized bya pivotable shutter member in said housing behind the said opening for blocking the movement of said water particles.

3. Dampening mechanism for use with printing devices. comprising a housing having an opening adapted to confront the plate cylinder of the press. means for maintaining a spray of water in said housing. a power driven propeller rotatably'. supported with n the housing and having apertured arms movable through the said spray to "in the-housing movable tointercept the movement of water particles toward the opening. and a baille plate adjustably movable into the path of said water particles behind the said opening.

4; A dampening mechanism for lithographic presses of the type including a rotating plate cylinder, said mechanism comprising a housing having a lower chamber and an upper chamber with an open end confronting a said plate cylinder, the said chambers being joined by a bight ber and out the opening thereof against a saidplate cylinder, and a movable shutter device in the said upper chamber and having a reciprocable driving connection with said plate cylinder whereby the shutter alternately opens and closes the said upper chamber to the movement of water particles toward said opening as said cylinder rotates.

5., A dampening mechanism for lithographic presses of the type: including a rotating plate cylinder comprising a housing having a lower chamber and an upper chamber with an open end confronting a said plate cylinder, the said chambersv being joined by a bight portion, means for spraying water into the lower chamber, a power driven propeller'in the lower chamber and having a plurality o1 screen mesh plates rotatable through the water spray to comminute the water, means for directing air into the said lower chamber past the said propeller means whereby the com minuted water will be carried around said bight portion into said upper chamber and out the opening thereof against a said plate cylinder, a

reciprocably mounted shutter device in the said upper chamber and having a reciprocating driving connection withsaid plate cylinder whereby the shutter alternately opens and closes the-said upper chamber to the movement of water particles toward said opening as said cylinder rotates, and baflle means including plates slidably mounted in side by side relation on said upper chamber for movement adjustably into the latter and across the path of water particles moving toward said opening. r

6. In lithographic presses and the like having a rotatable plate cylinder, dampening mechanism comprising a housing having a lower chamber and also an upper chamber with an open end adapted to confront a said plate cylinder, the said upper and lower chambers being Joined by a constricted bight or bend portion, means. for maintaining a water spray in the said lower chamber, means for atomizing the sprayed water including the rotatable propeller mounted in said lower chamber and having radially extended members movablethrough said spray to break,

up the water, means is: directing air into said lower chamber against said propeller toward and around said bight or bend portion whereby particles and the atomized water will be carriedinto said: upper chamber toward the said opening thereof, and means in said upper chamberfor controlling the movement of water particles toward said opening 7. Dampening mechanism for lithographic presses oi the type including a rotating plate ycylinder, said mechanism comprising a housing having a lower chamber and an upper chamber arcaosc and the latter having an exhaust opening confronting the plate surface of a'said plate cylinder, the said chambers being joined by arreduced bight portion, means including a tank having an apertured bottom wall and positioned on said lower chamber fonsbraying water into the latter, means for breaking up the water of said spray into fine particles, and means for directing a current of air through said lower chamber to carry water particles against and around said bight portion toward the said exhaust opening of said upper chamber.

8. Dampening mechanism for lithographic presses of the type including a rotating plate cylinder, said mechanism \comprising a housing having a lower chamber and an upper chamber and the latter having an exhaust opening confronting the plate' surface of a said plate cylinder, the said chambers being joined by a reduced bight portion, means including a tank having an apertured bottom wall and positioned on said lower chamber for spraying water into the latter, driven means in said lower chamber for breaking up the water of said spray into ilne particles, means for directing a current of air through said lower chamber to carry water particles around said bight portion toward the said exhaust opening of said upper chamber, and manually operable baiile means in said upper chamber for adjustably deflecting the movement of water particles relative to said exhaust opening.

9. Dampening mechanism for lithographic presses of the type including a rotating plate cylinder, saidmechanism comprising a housing having a lower chamber and an upper chamber, the latter having an exhaust opening confronting the plate surface of a said plate cylinder, the

said chambers being joined by a narrowihg bight,

portion, means including a tank having an apertured bottom wall and positioned on said lower chamber for spraying water into the latter, driven means in said housing for breaking up the water of said spray into fine. particles, means for directing a current of air through said lower chamber to carry water particles around said bight portion toward the said exhaust opening of said upper chamber, manually operable bailie means in said upperchamber' for adjustably obstructing the movement of water particles toward said exhaust opening, and means including a shutter reciprocably mounted in said upper chamber and having a reciprocating drive connection with said rotating plate cylinder for alternately opening and closing the said chamber to the passage of 1 water particles toward said exhaust opening.

'bai'iie plate with said lower-chamber to direct air against said propeller wheel and carry water. particles around said bight portion into said upper chamber, blowermeans for supplying air under pressure to said blower duct, the said lower chamber having a trough portion and drain means communicating therewith, a reciprocable shutter in said upper chamber including a member having a pairof oppositely disposed solid wall portions and a pair of oppositely disposed open wall portions respectively adjacent said solid portions and pivotable about a shaft member supported in the walls of said upper chamber whereby the said solid wall portions and apertured wall portions may be respectively rotated into or out of position across the said chamber to block the movement of water particles therethrough toward said opening, driving connections between said shutter member and said rotating plate cylinder for pivoting the said shutter alternately into open and closed position, the said driving connection including a presser finger having a pivoted connection with the shaft of said shutter and reciprocable by a cam driven by said plate cylinder, adjustable means for blocking the movement of water particles toward said opening in said upper chamber and including a plurality of plates slidably mounted in side by side relation in a wall of said upper chamber for movement into the latter across the path of water particles moving toward the opening, and means for holding the said plates in adjusted position.

11. Dampening mechanism for a device including a rotating cylinder, said mechanismcomprising a housing adapted for mountingadjacent a said cylinder and having an upper and a. lower chamber joined by an' arcuate wall portion, the said upper chamber having an exhaust opening confronting the surface of said cylinder, means in said housing providing a spray of water or like moistening substance, means for atomizlng said water including a pressure chamber having'communication through an aperturedmember into said lower chamber of said housing whereby air under pressure from an auxiliary source, may be directed through said spray to atomize the latter and drive atomized particles from said lower chamber past said arcuate wall portion and through the upper chamber out the exhaust opening thereof for impingement against said cylinder.

12. Dampening mechanism for printing presses and the like having a power-driven plate cylinder,

said mechanism'comprising a shallow housing of greater length than .depth and of a width adapted to extend axially across said cylinder and hav.-.

ing an opening disposed in confrontation with said cylinder, means providing afall of water in 'posit on said cylinder.

saidhousing at a point remote from said openonto the plate cylinder.

13. Dampening mechanism for printing presses and the like having a power-driven rotatable plate cylinder, said mechanism comprising a shallow housing of greater length than depth and of a width adapted to extend axially across said cylinder and having an opening disposed in confrontation with said cylinder, means providing a fall of water in said housing at a point remote from said opening, power driven means in said housing breaking up said water into fine particles, means directing air into said housing to drive said particles of water toward and through said opening onto the plate cylinder, together with means for blocking the movement of water particles onto said cylinder once during each revolution of the latter, said last-mentioned means including a shutter member in said housing behind said opening and movable into and out of particle blocking position therein periodically by drive mechanism cperably connecting said shutter member with said power driven plate cylinder.

14. Dampening mechanism for printing presses and the like having a power-driven plate cylinder, said mechanism comprising a housing having an opening confronting said cylinder, a source of water in said housing, a power-driven chopper in contact with said water and operable to atomize the same, together with air pressure means for carrying the atomized water toward and: through said opening for deposit onto said cylinder.

' i5. Dampening mechanism for printing presses and the like having a plate cylinder, said mechanism comprising a substantially U-shaped housing arranged before said cylinder and having the end portion of one of its arms provided with a discharge opening in confrontation with said cylinder, a source of water in the opposite arm portion of said housing, together with means for 'atomizing said water and carrying the atomized particles toward said discharge opening for de- ELMER c. Gammon. 

